Final render not showing full node setup
Looking at your node setup, I think it is because you have the wrong socket plugged into the Composite node. It should be coming from the same Add node that the Viewer node is also plugged into. Maybe you were testing earlier and forgot to change it back?

Also, you can enable Backdrop while in the compositor to update your changes as you work, this can save you the time of rendering everytime you need to try a certain setup or see changes.

See What is the difference between a Viewer and a Compositor node? for more information.